The liquid ring device is known in the prior art, with the concept existing in the patent art at least as early as U.S. Pat. No. 1,094,919 to Nash in 1914. In the Nash '919 device, a combustible gas is introduced into the device, compressed and ignited, with the expansion being used to provide mechanical energy.
In some situations in the prior art, the liquid ring device is used to compress gases at the expenditure of mechanical energy, while, in another type of operation, it is used as an expander to extract thermal energy from a working fluid as practical mechanical work. One application is the recuperation of the energy carried out by the exhaust gases from an internal combustion engine or a gas turbine.
Many other applications are envisioned, in which different working fluids are used. These include, but are certainly not limited to, recuperation processes involving furnace gases, foundry gases, residual industrial steam or geothermal gases, such as from a volcano. In yet other applications, the liquid ring device can be used as a prime mover or stand alone heat engine in conjunction with a hot gas generator of a suitable type. In general, the device is able to operate effectively, once the mode of operation and the energy source has been selected.
It is, however, not known in the prior art to perform more than one thermodynamic transformation in a single liquid ring device.